PWM: Correct misspellings of "module" in context of PWM

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Heiko Schocher <hs@denx.de>
diff --git a/README b/README
index 3682e8c..68d6a49 100644
--- a/README
+++ b/README
@@ -1361,7 +1361,7 @@
 
 - PWM Support:
 		CONFIG_PWM_IMX
-		Support for PWM modul on the imx6.
+		Support for PWM module on the imx6.
 
 - TPM Support:
 		CONFIG_TPM